Assay of blood or other biologic samples for target analytes

A method for detecting one or more different target analytes in a biologic fluid sample in a transparent tube, said method comprising the steps of:

• a) adding capture bodies to the sample, there being one group of capture bodies for each target analyte suspected to be in the sample, each group of capture bodies having a different specific gravity from each other group of capture bodies, and each capture body in each group thereof being coupled with a binding material which is specific to a first epitope or other binding site on one of the target analytes, whereby each of the different capture body/binding material couple groups is specific to a different one of the suspected target analytes;
• b) adding to said sample labeled antibodies or other binding material which is specific to another epitope or other binding site on each of said analytes to form a capture body/binding material couple and labeled binding material sample mixture;
• c) incubating the capture body/binding material and labeled binding material sample mixture;
• d) densimetrically separating the capture bodies into one or more distinct bands in the sample mixture;
• and
• e) determining which, if any of said bands exhibit the presence of a labeled antibody or other binding material, and therefore the presence of a target analyte.

A method for detecting one or more different target analytes in an anticoagulated whole blood sample in a transparent tube, said method comprising the steps of:

• a) adding capture bodies to the sample, there being one group of capture bodies for each target analyte suspected to be in the sample, each group of capture bodies having a different specific gravity from each other group of capture bodies, with all of the capture bodies having a specific gravity that will ensure that said capture bodies will settle into the red cell layer of the blood upon centrifugation of the sample in the tube, and each capture body in each group thereof being coupled with a binding material which is specific to one of the target analytes, whereby each of the different capture body/binding material couple groups is specific to a different one of the suspected target analytes;
• b) adding to said sample labeled antibodies or other binding material specific to said target analytes so as to form a capture body/binding material and labeled binding material sample mixture;
• c) incubating the capture body/binding material and labeled binding material sample mixture;
• d) centrifuging the sample so as to aggregate the capture bodies into one or more distinct bands;
• and
• e) determining which, if any of the bands exhibit the presence of a labeled antibody or other binding material, and therefore the presence of a target analyte.